The present invention relates to the general field of turbomachines in which the motion take-off bevel gear for driving the accessory gearbox is mounted on the trunnion of the high-pressure compressor shaft. The invention relates more precisely to making it easier to dismount the trunnion when the radial size of such an assembly is small.
Certain maintenance operations on a turbojet of the two-spool bypass type require the high-pressure spool module of the engine to be dismantled. These operations are generally made easier when it is possible to withdraw the high-pressure spool module rearwards without it being necessary to begin by removing the fan module.
Furthermore, in the context of developing turbojets of small size, it is necessary to incorporate within such engines a connection between an upstream trunnion of the high-pressure compressor shaft and a bevel gear that acts as a motion take off for driving the accessory gearbox of the turbojet. The motion take-off bevel gear is more precisely mounted around the high-pressure compressor shaft trunnion, being coupled thereto and supporting the inner ring of a ball bearing having its outer ring secured to the intermediate casing of the turbojet.
Incorporating the motion take-off bevel gear on the high-pressure compressor trunnion must enable the high-pressure spool module to be extracted rearwards, and more particularly must enable the trunnion of the high-pressure compressor shaft to be extracted rearwards relative to the bevel gear that itself must remain in place connected to the intermediate casing of the turbojet.
Nevertheless, when radial size is small because of the small size of the turbojet, removing the high-pressure spool module rearwards without it being necessary to begin by removing the fan module, and more precisely the bevel gear supporting the ball bearing, is found to be difficult if not impossible to achieve.